1. Field of the Invention
The present invention relates to an interposer and a method for manufacturing an interposer.
2. Discussion of the Background
A substrate called an interposer is used as an intermediate substrate on which multiple electronic components such as logic gates and memory are loaded. Electronic components loaded on the interposer are now being developed to have high density and surface-mounting methods such as BGA are used to draw multiple wires out of the electronic components.
In such an interposer for loading electronic components, wires are drawn from sites connecting one electronic component to another electronic component. Therefore, many wires are drawn within the interposer.
In addition, the amount of data handled by electronic components is increasing, and high-volume signal transmissions and fast signal transmissions need to be implemented in the interposer.
To implement high-volume signal transmissions and fast signal transmissions, it is necessary for the wire resistance between one electronic component and another electronic component to be weak.
Furthermore, in an interposer (such as one used in a substrate disposed in a mobile phone), because the space within which the interposer is disposed is small, it is necessary for the mounting height when electronic components are loaded to be small.
In Japanese Unexamined Patent Application Publication 2006-19433, an interposer with a penetrating through-hole in a supporting layer made of a silicon layer to load electronic components on both sides of a supporting substrate is described. In this interposer, wire layers laminated on one side of the supporting layer is provided, and the wire layer is formed with an insulating layer made of, for example, an organic material, a connecting electrode, and wiring in a predefined pattern. This interposer is an interposer with wiring formed in an organic insulating layer.
In addition, in Japanese Unexamined Patent Application Publication 2006-19433, an interposer with a method to load electronic components on both sides of a wire layer with wiring formed in the organic insulating layer is also described.
On the other hand, interposers with methods to form wiring in an insulating layer made of organic material using a wire-forming method (e.g., a damascene method) used in the semiconductor manufacturing process and load electronic components are also known.
The contents of the foregoing publication are incorporated herein by reference in their entirety.